Sequential system reducers can be mounted in any orientation, though there may in theory be slight advantages for longevity if they are installed in a certain orientation, would depend on reducer type and where inside it heavy ends are likely to build up. But since any slight advantage here would be completely overshadowed by the negative effect on reducer longevity of allowing the reducer to become a block of ice, it is better on vehicles with high risk of airlocks to mount the reducer in orientation that will best prevent airlocks.

I use loads of different types of filters on new installs, the handiest types are usually the smaller types, if I get too many of the big types in stock I'll fit them on vehicles I'm converting that have loads of space! The big type probably contains a gauzy type filter, reckon the small paper type do the best job of filtering but will need changing more often. Probably no advantage to being anorak about type of any filter, biggest job they do is prevent big bits of crispy heavy ends clogging injectors (vapour) or bits of foreign stuff from clogging reducer (liquid).

A new engine wouldn't put me off running it on LPG, but I'd be 100% the LPG system was working properly.

What to do with a new engine with a new cam... bottom ends like to be run in gently at first, cams are often better run in at high rpm. But nobody is going to fit an old cam in a new engine and swap the cam for a new one when then bottom end is run in, not in a pushrod engine anyway...

Simon

Don't quite follow, Marty. If you want to keep the back of the engine clear of LPG bits in order to allow better access to coil packs, splitting LPG pipe at the back of the engine (presumably to run pipes to Hana rails mounted under the manifold with gas pipes feeding to beneath the manifold from the rear) might not be a great way to go?

Given the limited options for injectors available with a Zavoli ECU would go with the Matrix setting.

No need for the balance pipe and won't make any difference.

Simon

They are that interchangeable but it is unlikely you'd see any difference updating to a more recent ECU and in some cases swapping to a more recent ECU can even prove a negative move.

200Gb worth of music on the hard drive in this laptop, backed up from another laptop from when I used to be a DJ. And this doesn't include the hundreds of CDs full of MP3s (maybe 100 tunes per CD) that I never put on a hard drive!

Simon

Yes it's an AEB2568B, which is an 'N' system, later type, the B suffix means it's 2nd generation N system (like I implied above!), it is the sequential slave type.

This is for intents and purposes fully interchangeable with even the most recent AEB2568 systems that are still made today.

If V6 software doesn't work, an earlier version such as v4.x or v3.x should. V5 software usually works with C/D suffix boards. As memory serves, B added sequential changeover, C added more advanced on board diagnostics, D is around when they became truly sequential and added connectivity to vehicle OBD2 to allow the LPG ECU to read petrol fuel trims.

Although it is termed sequential, on a B suffix it probably only reads petrol injector pulse duration from the front cylinder in each bank and bases gas pulse duration for all cylinders on the bank on only this reading, in which case it doesn't match the modern definition of truly sequential (wait for petrol pulse on each cylinder before beginning LPG injection pulse on that cylinder), but this isn't an issue on a P38.

Simon

I've heard that parking near certain types of transmission towers can lead to battery drain on P38s and on other vehicles...?

Hehe, I think Gilbert meant to link to this (http://www.rodsnsods.co.uk/forum/garage/medusa-206057)

and maybe this too (http://www.lpgforum.co.uk/viewtopic.php?f=33&t=13792&hilit=medusa)

MJFX singular injectors, perhaps even the larger MJ singular injectors, will fit below the manifold even without a spacer... but in my view there is neat while practical (in terms of future servicing etc) and then there is being slightly OTT neat (dismantling needed to access bits like filters etc, take the top off the engine to get to injectors..). It would take about equal time to fit injectors under the manifold as it does to fit them on top. Some engines might be considered a work of art by some people, other engines probably not... I don't think LPG components installed out of sight in the engine bay of a P38 outweighs positives of easy servicing, I don't think there is a technical advantage in fitting injectors under the manifold on a Rover V8.. If I thought there was a combination of neatness and technical advantage I would do it that way, otherwise the accessibility point wins out.

I believe manifold spacers for these engines are available off the shelf anyway? A sometimes slightly negative point of manifold spacers is that they add volume to the intake manifold, which on some engines (those that use TPS and AFM's rather than a MAP sensor as part of load input to the petrol ECU) will mean acceleration fuelling enrichment will then occur slightly ahead of ECU designer anticipated actual air flow increase past the inlet valves. For sure a negligible effect with a short spacer but one which could offset any negligible benefit from shortening LPG injector to manifold pipe lengths.

Seen a bit of rubbing on sound deadening material with injectors mounted on top, seems to be much worse if sound deadening material sags where it shouldn't.. but while we're talking about neatness we wouldn't want sound deadening material to sag either.

Easy to tell if an engine runs group or sequential injection in LPG software, some systems actually spell out what type of injection the engine runs, or another way to tell is by petrol injector duration - a normally aspirated group engine will idle at around 2ms and full load will be at around 8ms, these are half the usual figures for a sequential engine. Got me thinking now whether I have seen group injection on Gems P38s, I have seen sequential Gems, previous to your post I would have been more certain I'd seen group injection Gems on P38s too, still tend to think I have. As said above it's easy to tell if an individual vehicle runs sequential or group anyway. Most Rover V8's running sequential run with about 4ms pinj duration at idle with warmed engine at just over 0.4bar manifold pressure.

Edit - Last week I had a customer here with a P38, not one of my conversions but one that I repaired a couple of years ago (fitted new injectors on). As usual, the original installer had fitted the injectors atop the manifold without making holes for injector pipes to reach to the correct place in the lower manifold (so injectors fired gas into the upper manifold, several inches from the ideal place). Anyway, on this occasion the car came in because it was running very poorly on gas "It always ran beautiful since you fixed it but recently it went bad all of a sudden while I was driving". Turned out the ECU (AFC, which is really just a rebadged KME Diego) was driving a couple of injectors improperly (all peak current, no hold current). This had caused one of the injector coils to melt - easy to replace the injector coil but would have involved taking the upper manifold off if injectors were fitted under the manifold. Effected a temporary cure while it was here just by fitting another injector coil but warned the owner not to run on gas or at least to keep his eye on the 2 effected coils if he did run on gas (don't want it catching fire) before he returns for the ECU replacement (got a few of the more recent KME Nevo's in stock, Diego are being phased out but I'll get hold of one to make for most cost effective repair). A temporary repair made simple by easy access to components. Should he (unwisely) drive on gas in the meantime, should the coil melt again before I fit another ECU, no big deal changing the coil again (and I won't charge for the coil, got loads of loose ones for these injectors knocking about).

Simon

I never did get around to reading Rob's build thread Richard, seen the video though. Equally as clever as bonkers hehe.

Turbo'd Rover V8 in an old TVR

The negatives of long pipe lengths are not nearly as pronounced on a group injected engine as on a sequential injected engine (because group injection fires injectors twice as often, and in advance of inlet valves opening), so pipe lengths associates with fitting 2 x rails of 4 injectors on group injection Gems engines are not as critical as on sequential Bosch engines. When I convert a group injected Gems I mount a rail of 4 (down-flow) injectors to the UK driver side middle plenum allen bolt and the other rail to the passenger side front plenum allen bolt (throttle body prevents mounting rail in the middle on this side). Don't worry about keeping all pipes same length, the only 2 pipes that will be a bit on the long side anyway are those that run to the rear 2 cylinders on the passenger side, makes negligible difference on Gems particularly if you use 4mm ID pipe (low internal pipe volume compared to wider diameter pipes). The bosch/sequential is a different story, I mount side outlet injectors atop the bananas on these but remove metal from between the banana runners to allow pipes to fit through to the correct place (for outlets) in the lower part of the manifold beside petrol injectors.

Simon

I don't want to speak out of turn, especially not knowing the nature of the problem, but I've known P38s come up with gearbox warnings and shift gear incorrectly when there's been a problem with the throttle position sensor, a problem with the TPS could also cause the engine to cut out...

I appreciate people and firms that know their stuff (including Gilbert, wouldn't want this to read otherwise) and I've just had a look at the Ashcroft website. I have gearbox problems of my own on another type of vehicle, wondered if they might work on my type, they don't but I'm still impressed and found their site interesting.

Simon

Since you're not after the door or locks and the door can't be sold by the breakers until it is removed and they cannot unlock it either, couldn't you explain the situation to the breakers and get them to go in with an angle grinder?
Simon

Not useful but on the same subject - One of the easiest cars ever to get into without a key was the last shape Vauxhall Senator. Just pull up the plastic strip that runs the width across the outside of the door at the bottom of the window (thing with the outer felt window seal attached) to reveal the door lock and latch levers! Pull on either of those (can even get your finger in if not too chubby) and the door will open.. No damage, just slot the plastic trim back in place. I remember reading about Senators being unbelievably easy to get into in a newspaper, obviously the paper didn't explain how or why they were easy to get into, I found out a few years later when I bought my first Senator and had some work to do inside the door. Major design issue!

I think when I looked into it, like you said, I found cheap gear for the P38, equipment for the Disco started at about £1k.. I let 'Simons Services' use their tool, same name as myself, unrelated except I do their LPG work!

Thanks Gilbert, Yes I've replied on the Etagas thread.

Cheers.

Good going with the mates P38 Gilbert. Out of curiosity (no need at the moment), does anyone have the scan tool for setting / initialising suspension on P38s and Disco's? I once changed bags and height sensors on a Disco but then had to take it to a local Landrover specialist (whom I do all the LPG work for) for them to do the setting up with the tool. Did a bit of research before going there, apparently such tool for P38s is cheap and easily available (Ebay etc) but the different tool for a Disco is a lot more expensive to the extent wouldn't buy one unless using it regularly for paying customers?

Simon

Hmm, well without a stamp the jury is still out on whether this is a preN or N system. There is yet another way to tell... If there is a connection to TPS (likely a blue and yellow wire) it will be a preN system.

I've converted a few P38's myself years ago using a sandwich plate.. but I made up heat shields for the injectors, fitted a reducer that is more on top of the job for the V8, used another gasket with the sandwich plate and mapped it properly! ;-) With manifold nozzles in the correct place near petrol injectors, short pipes will run to injectors sat at either side of the engine, OK except this can mean they're above exhaust manifolds so pick up both infrared and convection heat and with rails widely apart at each side of the engine it isn't a complete no-brainer keeping injector rail feed pipe lengths to the reducer both the same length (not a biggie really!).

It is possible to convert these engines in the same way without even using a sandwich plate, can simply machine the ribs on the rocker covers and the underside of the upper manifold a bit to make room for 5mm internal diameter pipes to run to injectors at either side of the engine. 4mm pipe will fit even without the machining but would mean using different injectors (Matrix have 6mm outlets, 6mm or 5mm pipe will fit but 4mm won't). I've converted some P38s with both of these methods (the machining / the 4mm pipe) too.

These days I machine metal from between the finger spans of the banana manifold, so injectors can sit atop the engine with pipes running to nozzles in the manifold in the correct place through the machined holes in the upper manifold, doing away with the need for heat shields and keeping pipe lengths (including between reducer and each injector rail) all similar..

Simon

That's an AEB025 pressure sensor, so is the later (and latest) type. Difficult to see the attaching wiring, if the wiring doesn't look tampered with and there is no adaptor (to adapt from old type AEB013 connector on old type wiring loom to AEB025 type connector, i.e. a short bit of wire with a plug on each end) then I would suspect you have an N type ECU (so is slave / much more common type similar to even the latest type systems). If that's the case then, as explained above, the V6 software is very likely to work with it. Even systems fitted 11 years ago are unlikely to be pre-N type. One way to confirm would be to check your petrol fuel trims while running on gas - if fuel trims (when running on gas) don't drift to one extreme or the other then it will almost certainly be N type, if your fuel trims do drift to one extreme (rich or lean) when running on gas then this doesn't prove that you have pre-N type because this could also be explained by there being a problem with your LPG system or with how it is calibrated. Yet another way to check is by looking on the back of the LPG ECU, if it is N type it will be stamped AEB2568, I suspect yours will have a B or C suffix at the end of that board code too (still implying N type).

Simon

The BMW 4.4 engine has a couple of wide diameter breather pipes that run across the top of the back of the engine. It seems common for these to perish, some people put the perishing down to the material being incompatible with ethanol that is in modern day petrol, others put perishing down to material not being compatible with oil/HC's that inevitably make there way into breather pipes. At the time of design there probably wasn't ethanol in petrol, I tend to agree with the ethanol idea because before ethanol was in petrol we LPG installers could use LPG pipe for petrol but modern petrol causes LPG pipe to similarly perish, similarly the BMW4.4 breather pipes didn't seem to have a problem before ethanol. Since the pipes feed into the back end of the inlet manifold, leaks in them amount to a vacuum leak. I've changed them on a number of L322's that I've converted to LPG - even if there isn't a leak to start with, moving perished pipes around during other work can cause them to break up. By perishing I mean the pipes tend to become gummy, almost like they're melting, become more flexible and easily tearable. There comes a point in the process where in a cross section of pipe it would be difficult to make out where the pipe starts and the gum/oil ends. The pipes are fairly easy for a home mechanic to change and, as I remember, cost a total of around £35 from BMW dealers who seem quite used to supplying these specific pipes (common problem).

Swapping tranny fluid is something I do early on all cars I buy, particularly in autos if it doesn't look or feel like I think it should, I'll also swap coolant, even brake fluid if that looks old. But there is the possibility of causing an old box to whine or affect the shift by swapping in new fluids even of the correct spec. And getting correct spec can involve a bit of research, especially on boxes that were supposedly filled for life.

Simon

Sometimes when plugs have been cut off it's because they corroded, so someone might cut the plug off to just screw wires together.

Agreed with Gilbert it could be a pre-N system, there is no N designation on the ECU sticker... but if it is pre-N it will be a rare example. Most pre-N systems have pressure sensor built into the ECU (so pipes attached directly to the ECU), most of the rest will have (at least originally) been fitted with the (external) AEB013 pressure sensor, even early N systems used the AEB013 sensor. Most pre-N internal and AEB013 external sensors will have failed by now, not easy to swap ECU internal pressure sensors but easy enough to swap an AEB013 for the later AEB025 type that is still used today (means swapping connecting plugs and changing settings in software though). Most pre N systems used ECUs with only 4 injector driving channels, for vehicles with more than 4 cylinders an external injector driver was (supposedly) added to the system (not always fitted, some installers bodged by just wiring 2 injectors in parallel to one driver channel).

Though V6 software will work on most N systems, some early N systems need software within a certain version range.

Pre N system ECU's work in a very different way to N systems, need different software altogether and are calibrated very differently. N type work as a slave to the petrol system, read petrol injector pulse duration and add fiddle factors as per user mapping to arrive at gas injector duration, so gas injector duration is calculated based on input from the petrol system. Pre N type work standalone, output specific gas injector pulse duration described by the installer's map which is based on engine rpm and engine vacuum, automatic closed loop operation is afforded by connection to lambda input (necessity).

Simon

Don't splash around the LPG ECU or pressure sensor mate!

Simon